Three-position signal.



WITNESEEE W. V. MOAK.

THREE POSITION SIGNAL.

APPLICATION FILED SEPT. 25, 1908.

Patented Apr. 27, 1909.

INVENTUR WILLIAM VNHJAK.

ATTY

W. V; MOAK.

THREE POSITION SIGNAL.

APPLICATION IILED SEPT. 25, 1908.

Patented Apr. 27, 1909.

3 SHEETS-SHEET 3.

INVENTEIR WILLIAM V. MEIAK, BYMVLUKTTY.

WITNESSES:

l wrLLmi/I' v. Moan, or SCOHENEOTADY, NEW YORK, ASSIGNOR 'ro GENERAL ELECTRI hours-NY, a CORPORATION OF NEW YORK.

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s" s r-mar FFICE.

j v 1 'rrrann-rosrrron SIGNAL.

Application filed se arate: 25. 1908. Serial No. 464,805.

" (To all whom it may concemf Be it known that I, VVI'LLIAM V. MOAK, a

citizen of the United States, residin at Schenectady, county of Schenectady, gtate of New York, have invented certain new *andfuseful Improvements in Three- Position Signals, of which the following is a specification.-

invention relates to three-position semaphore 'signals,.and its object is to pro-- duce a signal of this character, which is re *l-iable, simple and eflicient.

f to drivejt, and for holding the semaphore arm at clear and caution positions. .There' f is another type of signal in which a single magnet performs the function of clutching .tlie'motor tothe "arm, and of holding the arm in position after the motor circuit has been opened; but this type of signal has not heretofore been well adapted to three-posi tion operation for the following reasons.

It is desirable that a signal should be able to return from clear to caution position, and stop there,- without first going to danger position, so that the clutch or slot magnet should be able to releasethe semaphore arm at clear position and stop --it whenit has reached caution position. If the arm is permitted to fall rapidly from clear position by gravity, the amount of power required to stop the signal at caution position is much. greater than that required to hold the signal in clear or caution position, so

that it has heretofore been necessary either tomake the clutch or slot magnet much Jstronger' than is necessary for holding the signal in position, which wastes power, or to. make the movement of the signal from clear to danger quite slow, atleast whilemoving through caution position, which is *sometimes objectionable. from an operating standpoint.

By my invention I am enabled to make the retardation of the signal, when moving by gravity, no greater than :in the usual two-position signal; and at the same time to avoid any increase in the amount of'current consumed by thesl'ot magnet when holding the signal at clear or caution. I accom- DllSh this by providing means for momen- Specification of Letters Patent.

Patented April 27, 1909.

tarily increasing'the strength of the slot magnet above normal for stopping the arm before it reaches danger position in moving from clear to caution.

It has been often customary heretofore to provide the slot.magnets for signals with auxiliary coils which are connected in series with the motor circuit, so as to make the slot magnets stronger whilethe motor is driving the semaphore arm. I utilize this samearrangement, to increase momentarily the strength of the slot magnet to catch the signal at cautiomby so spacing the stops,

which are engaged by the catch controlled ,by the slot magnet, that in dropping from clear. tocaution position the semaphore arm passes slightly beyond gaution position, so that the motor circuit is momentarily closed. 'lhis'resultafirst, in strengthening the slot magnet above normal, so as to enable it to stop the signal, and secondly in energizing the motor to cause it to make the .few revolutions necessary for returning the arm to caution posit-ion. Since three-posttion signals are ordinarily operated wlth 45 displacement between caution ,and each of' the other two positions, a rotary slot mech anism with seven stops is well adapted for giving the desired result; In dropping back from one stop to the next, in moving from clearto caution, the semaphore arm moves through approximately 51-,that

is,"6-} beyond caution position; and this movement sufficient to close the motor circuit withtheresults above described.

My invention will best be understood by reference to the accompanying drawings, in which- Figurel shows an elevation of a signal mechanism for a three-position signal arranged in accordance with my invention,

the semaphore arm being shown at clear position; Fig. 2 shows a similar view with the semaphore arm in caution position; Fig. 3 is-a diagram of circuit connections; and Fig. 4 is a detail view of the slot mechanism.

In the drawings, A. represents an electric motor, which drives through suitable speedreducing gearing a gear wheel B, which serves as a driving member for the sema-' phore arm, and is loosely mounted on the shaft C, to which the semaphore arm D 18 secured. This drive-wheel is provided with a series of pins or stops Z), which are evenly i semaphore shaft C, and which carries a slot 6 into engagement with the next pin or stop or clutch mechanism comprising a pawl or catch 6, adapted to be moved into and out of the path of the stops b on the drivewheel.

The construction of the slot mechanism is best shown in.Fig. l. F represents the main winding of the slot magnet, whichis provided with auxiliary coils f, which are con-' nected in-the motor circuit. The armature f is carried at the end of a lever e pivoted on-the arm E at if. The-short arm of the lever e is pivotally connected to one end of the pawl or catch .6, which is supported on a link 6 pivoted at e on the arm E. As long as the slot magnets are energized, the catch 0 is held i. vthe position shown. If the slotimagnets are deenergized, the pressure of the catch e on the pins 6 rocks the lever 6 so as to move the armature f away from the magnet poles,and to permit the Withdrawal of catch 6 from the path of the pins 7). 'G is the usual-dashpot. H represents se ments k on the semaphore shaft and contr dl the circuits of the motor and clutch magnets.

Since .the pins 7) are seven in number,"and equally spaced, they are separated by an arc of about 51-18. Therefore, if the signal stands in clear position, as shown iri Fig. 1, and the slot magnet is denergized, the sig nal arm must move 51% to bring the catch 6. The contacts H and h are so arranged that the motor circuit is closed when the semaphore arm has moved approximately or-a little over l5, so that both the motor and the series slotj'jicoils will be energized when the catch 6 engages the next pin 6, so that the strength of the slot magnet will be increased above normal, and the motor will operate sutficiently to return the drive-wheel a few degrees? so as to break the motor oilcuit and leave the semaphore arm in caution position, as shown in Fig. 2.' If the signal is to pass from clear to danger'position, the slot magnetis, of course, not en- 'ergized when caution position is; reached, so

' that the catch 6 simply slides over one m I) without resistance: In order to prevent a Manhattan.

hammering of the armature f on the poles of the slot magnet, when the catche passes over a pin in this manner, the inner surfaces of the pins 12 are beveled, as shown, so that though the outward movement of the armature f is ,rapid, I the return movement is much slower. Theouter face of the pawl e, sliding along which it is passing, allows the armature f to return gently against'the poles of the-slot magnet.

tact segments fixed contacts which engage contact theinner'surface of the pin A suitable arrangement of the control circuits for thesignal is shown in Fig. 3. The motor A is shown provided'with a main series field a and an auxiliary shunt field a, which is used only forelectric braking'on reaching clear positiom The-main shunt and auxiliary series windings of the slot magnet are indicated by 'F and f, respectively. In order to make the diagram plain, the stationary contacts H andmovable conh are shown developed on a plane surface. The. positions of the tacts for the different positions of the signal are indicated in dotted lines, which for danger, caution and clear positions, are num- J represents the track relay connected to the rails K of a block. L represents the line relay controlled by the signal of the block in advance.

With a train 1n the block, as indicated in the'diagram, the track relay J is denergized, and the signal stands at danger. When the train passes into the next block, denergizing the line relay L and ener izing the track relay J, a circuit is closed from the. upper terminal of batteryl, through the series slot winding f, series field a, motor armature A,

contacts H, andarm'ature of track rela J, to the lower terminal ofthe battery. T e circuit of the main slot'winding F is, also closed across the battery throu h thecontacts H and armatureof track re ay J. The motor consequently starts and drives the signal toward caution position. When caution. position is reached, the motor circuit is opened, whiledthe main slot winding F remains energized to hold the signal at caution. When the trainproceeds out'of the block in ad- Vance, the line .relay L and the motor circuit is again closed through the armatures of the track relay and line relay in series. In moving from caution to clear position, the circuit of the main slot winding F is also shifted, so as to make it include the armature of the line relay L. When clear position is reached, the motor is disconnected from the battery, and its armature is short-c rcuited, so that the motor acts 'as an electric brake to stop the signal. Now,

if a train, after having left the block in ad- V vance, should back'into it again, so that th-i.

should return from clear the line relay L is dethecircuit of the main semaphore arm-D to caution posltion,

energized, opening slot'winding F. This circuit is again closedthrough the contacts .H and armature of track relay J, before reaching caution position. The. catch carried by the semaphore arm does not, however, engage a stop on the drive-wheel until the semaphore arm has assed a few degrees is again energized beyond caution posi tion, so that the motor circuit is again closed. The series slot winding fis thus fully enersa bered l, 2- and 3, respectively.- I represents I the battery for supplying current to the ..motor and slot magnet.

gized at the time the signal is stopped, and the motor makes a few revolutions to return the arm to caution position, when the motor circuit is again opened by the contacts H.

I do not desire to limit myself to the particular construction and arrangement of parts here shown, but aim in the appended claims to cover all modifications which are within the scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States, is,

1. A three-position semaphore signal, com prising an electric motor, a driving member driven by the motor, a semaphore arm. means for clutching said member to said arm to drive it from danger to caution and to clear and to hold said arm at caution or at clear and for unclutching said arm to permit itto move from clear to caution and to danger, an electromagnet controlling said means, and means for increasing the strength of said electromagnet above normal for stopping sa id arm before it reaches danger position in moving from clear to caution.

A three-position semaphore signal, comprising an electric motor', a driving member driven by the motor, a semaphore arm, means for clutching said member to said arm to drive it from danger to caution and to clear and to hold said arm at caution or at clear and for unclutching said arm to permit it to move from clear to caution and to danger, an electromagnet controlling saidmeans, a

Winding on said electromagnet which is deenergized when the arm is being held at clear or caution, and contacts and COl1116C-.

tions arranged to energize said winding to strengthen said magnet to stop said arm before it reaches danger position in moving from clear to caution.

} A three-position semaphore signal, comprising an electric motor, a rotary driving member driven by the motor, a semaphore arm, a series of stops and a catch movable into and out of engagement with said stops,

said stops and catch moving one with said driving member and the other withsaid semaphore arm, an electromagnet controlling said catch, and means for increasing the strength of said electroinagnet above normal for stopping said arm before it reaches danger position in moving from clear to caution position.

4. A three-position semaphore signal, comprising an electric motor, a rotary driving member driven by the motor, a semaphore arm, a series of stops and a catch movable into and out of engagement with said stops, said stops and catch moving one with said driving member and the other with said semaphore arm, an electroma 'net controlling said catch, a winding on said electromagnet which is deenergized when the arm is being held at clear or caution, and contacts and connections arranged to energize said winding to strengthen said magnet to stop said arm before it rea hes danger position in moving from clear to cautio A three-position semaphore signal, comprising an electric motor, a rotary driving member driven by said motor, a semaphore arm, a series of stops and a catch movable into and out of engagement with said stops. said stops and catch moving one with said driving member and the other with said semaphore arm, an 'eldctromagnet controlling said ratch and having a plurality of windings one of which is in series with the motor, and contacts for closing the motor circuit when said 'arm has moved approximately forty-five degrees in passing from clear to caution, said. stops being separated by more than forty-five degrees but less than ninety, whereby the arm in moving'from clear to caution passes beyond caution position and the motor circuit is closed to strengthen said electromagnet for stopping the arm and to energize the motor for returning the arm to caution position.

6. A three-position semaphore signal, comprising an electric motor, a rotary driving mcmberdriven by the motor, a semaphore arm, a series of stops substantially evenly spaced and seven in number and a catch movable into and out'of engagement with said stops successively, said stops and catch moving one with said member and the other with said arm, an electromagnet controlling said catch and having a plurality.

of windings, one of which is in series with said motor, and contacts for closing the motor circuit when said arm has moved approximately forty-five degrees in passing from clear to caution In witness whereof, I have hereunto set my hand this 24th day of September, 1908.

WILLIAM V. MOAKM Witnesses BENJAMIN B. HULL, MARGARET E; WOOLLEY. 

